Refactor the function group_get_user_groups(). Bug 1304053

 - Add function comment,
 - Make it compatible to old calls
 - Sort the list out of the queries to reduce the MYSQL queries
 - Set the sort default value when displaying the my group side bar

Change-Id: I50decadcebe8a5cb38706809d70a784e6694c46d
Signed-off-by: Son Nguyen <son.nguyen@catalyst.net.nz>

htdocs/blocktype/mygroups/lib.php

@@ -81,7 +81,13 @@ class PluginBlocktypeMyGroups extends SystemBlocktype {
         $smarty = smarty_core();
         require_once('group.php');
         // Group stuff
-        list($usergroups, $count) = group_get_user_groups($userid, null, $sort, $limit);
+        if (!empty($limit)) {
+            list($usergroups, $count) = group_get_user_groups($userid, null, $sort, $limit, 0);
+        }
+        else {
+            $usergroups = group_get_user_groups($userid, null, $sort);
+            $count = count($usergroups);
+        }
         foreach ($usergroups as $group) {
             $group->roledisplay = get_string($group->role, 'grouptype.'.$group->grouptype);
         }

htdocs/blocktype/mygroups/mygroups.json.php

@@ -46,10 +46,16 @@ if (!$userid) {
 $smarty = smarty_core();
 
 // Group stuff
-list($usergroups, $count) = group_get_user_groups($userid, null, $sort, $limit);
+if (!empty($limit)) {
+    list($usergroups, $count) = group_get_user_groups($userid, null, $sort, $limit, $offset);
+}
+else {
+    $usergroups = group_get_user_groups($userid, null, $sort);
+    $count = count($usergroups);
+}
 
 foreach ($usergroups as $group) {
-    $group->roledisplay = get_string($group->role, 'grouptype.'.$group->grouptype);
+    $group->roledisplay = get_string($group->role, 'grouptype.' . $group->grouptype);
 }
 $groups = array('data' => $usergroups,
                 'count' => $count,

htdocs/lib/form/elements/filebrowser.php

@@ -336,7 +336,7 @@ function pieform_element_filebrowser_configure_tabs($viewowner, $prefix) {
         if ($groups = $USER->get('grouproles')) {
             $tabs['group'] = get_string('groupfiles', 'artefact.file');
             require_once(get_config('libroot') . 'group.php');
-            list($groups) = group_get_user_groups($USER->get('id'));
+            $groups = group_get_user_groups($USER->get('id'));
             if ($selectedtab == 'group') {
                 if (!$selectedsubtab = (int) param_variable($prefix . '_ownerid', 0)) {
                     $selectedsubtab = $groups[0]->id;

htdocs/lib/form/elements/viewacl.php

@@ -109,8 +109,7 @@ function pieform_element_viewacl(Pieform $form, $element) {
         'preset' => true
     );
     $mygroups = array();
-    list($usergroups) = group_get_user_groups($USER->get('id'));
-    foreach ($usergroups as $g) {
+    foreach (group_get_user_groups($USER->get('id')) as $g) {
         $group = array(
             'type' => 'group',
             'id'   => $g->id,

htdocs/lib/group.php

@@ -1990,8 +1990,23 @@ function group_get_associated_groups($userid, $filter='all', $limit=20, $offset=
 
 }
 
-
-function group_get_user_groups($userid=null, $roles=null, $sort=null, $limit=null) {
+/**
+ * returns a list of groups of a user by $userid or the current logged in user, given $roles from cache or database
+ * where $roles is the list of the user's role in a group
+ * if the user id is null, the logged in user will take into account
+ * if $roles is empty, all groups of the user will be returned
+ *
+ * @param int $userid
+ * @param array $roles
+ * @param string $sort is 'earliest', 'latest', or 'alphabetical'(default),
+ *     sorts the list of groups based on the date the user joined the group or group name
+ *     if empty, the list will be sorted by group name, admin role first
+ * @param int $limit  The number of groups to display per page (page size)
+ * @param int $offset The first group index in the current page to display
+ * @param boolean $fromcache if yes, try to return the list from the cache first
+ *                             or no, force to query database and update the cache
+ */
+function group_get_user_groups($userid=null, $roles=null, $sort=null, $limit=null, $offset=0, $fromcache=true) {
     global $USER;
 
     static $usergroups = array();
@@ -2002,14 +2017,7 @@ function group_get_user_groups($userid=null, $roles=null, $sort=null, $limit=nul
         $userid = $loggedinid;
     }
 
-    if (!isset($usergroups[$userid]) || !empty($sort)) {
-        $order = '';
-        if ($sort == 'earliest') {
-            $order = 'gm.ctime ASC, ';
-        }
-        if ($sort == 'latest') {
-            $order = 'gm.ctime DESC, ';
-        }
+    if (!$fromcache || !isset($usergroups[$userid])) {
 
         $groups = get_records_sql_array("
             SELECT g.id, g.name, gm.role, g.jointype, g.request, g.grouptype, gtr.see_submitted_views, g.category,
@@ -2020,18 +2028,49 @@ function group_get_user_groups($userid=null, $roles=null, $sort=null, $limit=nul
                 LEFT OUTER JOIN {group_member} gm1 ON gm1.group = gm.group AND gm1.member = ?
             WHERE gm.member = ?
                 AND g.deleted = 0
-            ORDER BY " . $order . "g.name, gm.role = 'admin' DESC, gm.role, g.id",
+            ORDER BY g.name, gm.role = 'admin' DESC, gm.role, g.id",
             array($loggedinid, $userid)
         );
         $usergroups[$userid] = $groups ? $groups : array();
     }
 
+    if (!empty($sort)) {
+        // Sort the list of groups based on the date the user joined the group
+        if ($sort == 'earliest') {
+            usort($usergroups[$userid],
+                function ($g1, $g2) {
+                    if ($g1->ctime == $g2->ctime) {
+                        return ($g1->name < $g2->name) ? -1 : 1;
+                    }
+                    return ($g1->ctime < $g2->ctime) ? -1 : 1;
+                }
+            );
+        }
+        else if ($sort == 'latest') {
+            usort($usergroups[$userid],
+                function ($g1, $g2) {
+                    if ($g1->ctime == $g2->ctime) {
+                        return ($g1->name < $g2->name) ? -1 : 1;
+                    }
+                    return ($g1->ctime > $g2->ctime) ? -1 : 1;
+                }
+            );
+        }
+        else if ($sort == 'alphabetical') {
+            // Do nothing, the list sorted by the SQL query
+        }
+        else {
+            throw new SystemException('Unknown sort flag: "' . $sort . '"');
+        }
+    }
+
     if (empty($roles) && $userid == $loggedinid) {
         $count = count($usergroups[$userid]);
         if (!empty($limit)) {
-            $usergroups[$userid] = array_slice($usergroups[$userid], 0, $limit);
+            $truncatedusergroups = array_slice($usergroups[$userid], $offset, $limit);
+            return array($truncatedusergroups, $count);
         }
-        return array($usergroups[$userid], $count);
+        return $usergroups[$userid];
     }
 
     $filtered = array();
@@ -2045,16 +2084,16 @@ function group_get_user_groups($userid=null, $roles=null, $sort=null, $limit=nul
     }
     $count = count($filtered);
     if (!empty($limit)) {
-        array_slice($filtered, 0, $limit);
+        $filtered = array_slice($filtered, $offset, $limit);
+        return array($filtered, $count);
     }
-    return array($filtered, $count);
+    return $filtered;
 }
 
 function group_get_user_admintutor_groups() {
     $groups = array();
 
-    list($usergroups) = group_get_user_groups();
-    foreach ($usergroups as $g) {
+    foreach (group_get_user_groups() as $g) {
         if ($g->role == 'admin' || $g->see_submitted_views) {
             $groups[] = $g;
         }

htdocs/lib/mahara.php

@@ -2928,22 +2928,28 @@ function profile_sideblock() {
     $data['pendingfriends'] = count_records('usr_friend_request', 'owner', $USER->get('id'));
     $data['pendingfriendsmessage'] = $data['pendingfriends'] == 1 ? get_string('pendingfriend') : get_string('pendingfriends');
     // Check if we want to limit the displayed groups by the account setting
-    $sort = null;
     $limitto = null;
     if ($limit = $USER->get_account_preference('groupsideblockmaxgroups')) {
-        if ($sortorder = $USER->get_account_preference('groupsideblocksortby')) {
-            $sort = $sortorder;
-        }
         if (!empty($limit)) {
-            $limitto = $limit;
+            $limitto = intval($limit);
         }
     }
-    list($data['groups'], $total) = group_get_user_groups($USER->get('id'), null, $sort, $limitto);
-    if (isset($limit) && $limit == '0') {
+    $sort = null;
+    if ($sortorder = $USER->get_account_preference('groupsideblocksortby')) {
+        $sort = $sortorder;
+    }
+    if ($limitto === null) {
+        $data['groups'] = group_get_user_groups($USER->get('id'), null, $sort);
+        $total = count($data['groups']);
+    }
+    else if ($limitto === 0) {
         $data['groups'] = null;
     }
+    else {
+        list($data['groups'], $total) = group_get_user_groups($USER->get('id'), null, $sort, $limitto);
+    }
     $limitstr = '';
-    if (!empty($limitto) && intval($limitto) < $total) {
+    if (!empty($limitto) && $limitto < $total) {
         switch ($sort) {
             case 'earliest':
                 $limitstr = get_string('numberofmygroupsshowingearliest', 'blocktype.mygroups', $limitto, $total);
@@ -2951,7 +2957,7 @@ function profile_sideblock() {
             case 'latest':
                 $limitstr = get_string('numberofmygroupsshowinglatest', 'blocktype.mygroups', $limitto, $total);
                 break;
-            case 'alphabetical':
+            default:
                 $limitstr = get_string('numberofmygroupsshowing', 'blocktype.mygroups', $limitto, $total);
                 break;
         }

htdocs/search/elasticsearch/lib.php

@@ -912,8 +912,7 @@ class ElasticsearchFilterAcl extends \Elastica\Filter\BoolOr
 
     private function getGroupsList(){
         $list = array();
-        list($groups) = group_get_user_groups($this->user->get('id'));
-        foreach ($groups as $group) {
+        foreach (group_get_user_groups($this->user->get('id')) as $group) {
             $list[$group->role][] = $group->id;
             $list['member'][] = $group->id;
         }

htdocs/user/view.php

@@ -144,8 +144,7 @@ if (!empty($loggedinid) && $loggedinid != $userid) {
     // - the logged in user has a role which is allowed to assess submitted views, or
     // - the logged in user is a member & is allowed to invite friends (when the displayed user is a friend)
     $groups = array();
-    list($usergroups) = group_get_user_groups();
-    foreach ($usergroups as $g) {
+    foreach (group_get_user_groups() as $g) {
         if ($g->role == 'admin' || $g->see_submitted_views || ($is_friend && $g->invitefriends)) {
             $groups[] = $g;
         }